The present invention relates to a wick for burning a liquid fuel.
The wicks for burning a liquid fuel used in liquid fuel burning equipment such as kerosene stoves have a flame forming portion made of a fabric knitted or woven from a mixture of yarns mainly consisting of glass fibers mix-spun with staple fibers or the like. The glass fibers used in these conventional wicks have diameters as large as around 9.mu.. In these conventional wicks, the gaps between the yarn threads is considerably large because the wicks are made of knitted or woven fabric. In addition, the flammable content such as staple fibers is burnt when the wick is frequently used causing the gaps between adjacent glass fibers of each yarn thread to further increase. Large gaps between the adjacent yarns and between the adjacent glass fibers make, in combination with the large diameters of the glass fibers, the size of capillary gaps formed in the wick considerably large. In consequence, the capillary action of the wick is very much reduced. This means that as the height of the wick portion above the surface of the liquid fuel such as kerosene becomes higher, the amount of the liquid fuel in the upper end portion of the wick is decreased. Therefore, when an inferior kerosene is used as the fuel, the temperature of the combustion section of the wick is inconveniently increased to permit formation of tar.
In addition, since the combustion section and the fuel capillary supply section of the wick are formed integrally, a series of troublesome work such as demounting of heat shielding plate, wick cover sleeve and other parts is required for renewing the wick when the latter has become unusable due to generation of tar due to the use of a fuel of inferior quality. The conventional wicks impose also a problem of high maintenance costs on the user because the whole part of the wick including still unburnt fuel capillary supply portion has to be renewed when the wick has become unusable.